I want to highly recommend this book and its approach [and I have, in the past, to friends] but I would now hesitate after 1 year with Maffetone. Today, I find myself unsure of the principles and frustrated with the gaps left open within this book. Let me summarize what I have found that I believe is very worthwhile and/or appealing:
* The principle that fat utilization must be maximized for peak endurance performance
* Dietary principles of reducing excessive carbohydrate intake and eliminating allergenic foods (such as gluten) for optimal health
* The appeal of an relatively easy-intensity way to good health and peak performance
As one who'd tried higher intensity training efforts for amateur running and cycling, I found Maffetone's message very appealing. I especially gravitated to it after cutting the carbohydrate in my diet which limited my access to higher intensity training. I tried adhering to his heart-rate based formula to keep my training intensities within the prescribed training band and started, after 3 months, to see slivers of success in training. On the treadmill, over time, I eventually saw a 0.5 mph improvement in pace at the same heart rate. On the bicycle trainer, a 30 watt improvement at Maff heart rates. These changes were very gradual, however, as I train only 3-4 hours / week. In fact, for 3 months, I saw virtually NO improvement at all. Now, I was not a perfect adherent to the principle of NO anaerobic work; I did weight train, but only 2x a week and only for 30 minutes at a time (actual time in the act of weight lifting was likely only 15 min a week with rest-between-sets time factored out). Does this invalidate my results? I should hope that the human body is not so frail that a mere lifting of something heavy a couple of times, on off days, is enough to completely destroy aerobic adaptations. What a weak species we would be. Consider that I'm not training 10-15 hours a week as many, more dedicated runners might be doing. Either way, you should know from where I'm coming from. Maffetone does indicate that he considers any aerobic training in excess of his prescribed heart rate formula or weight training of ANY kind (regardless of the heart rate) to be `anaerobic' work that could interfere or destroy aerobic adaptations. Nevertheless, I do feel that my training schedule, overall, was light enough that I was exercising well within my recover abilities. Nevertheless, my results on his program were modest at best. I sleep well, eat fantastically healthy compared to the average Joe (frutis, vegetables, low carb diet, omega-3s daily, lean meats, healthy amounts of good fats --- you get the point). Even though I did see what could be regarded as "significant" improvement in a couple of markers, I found that very little of this translated during races. As such, let me summarize the issues I've come to see with the Maffetone method:
* The 180 formula does NOT take into account individual variations in heart rate stroke volume or muscle physiology for different sports. Maffetone does not consider maximum heart rate nor resting heart rate to be significant. Instead, his formulas are purely a function of age and a few modifiers that have nothing to do with your heart's individual characteristics. This seems to fly in the face of common sense and science. If you have a larger heart with a greater stroke volume, then you will be pumping more blood at 140 beats, doing more work and feeling a higher level of perceived exertion (and likely have a lower max heart rate) than someone with a smaller heart who, at 140 beats, might feel as though they are barely working. This is why most heart rate-based programs factor in maximum (and some resting heart rate) - the level of exertion for someone with a max hr at 170 will be different than someone with a max of 200. In addition, Maffetone does not consider "perceived exertion" which varies between sports at a given heart rate, to be significant: one Maff heart rate for all. Really? A swimmer should use the same heart rate as a runner though we know that the muscle composition of the upper body is likely very different than the legs (which are designed for long-range locomotion)? Isn't that why you would likely have a higher perceived exertion at a given heart rate in swimming or perhaps cycling than running - different muscle fiber composition? I should think so but Maff believes that the same metabolic demands are being made so the training effect is identical. I dare to say that this is likely to be proved wrong by science but I only dispute it today by my intuition that "perceived " exertion is a real phenomenon that is being ignored by Maffetone. He does not present a cogent explanation for ignoring it other than saying that weight bearing sports produce a higher perceived exertion. Weak. It certainly doesn't explain the difference between cycling and swimming which are both non-weight bearing but generate different perceived exertions. I strongly suspect that more sugar-burning aerobic fibers are involved in swimming given the use of upper body muscles and, hence, the higher perceived exertion than running (which uses muscles with a higher % of red muscle fibers) at a given heart rate but that's' for a physiologist to work out. I don't buy Maff's explanation at all, however.
* There is absolutely no guidance with regard to training volumes for different sports what-so-ever. Inexcusable. On the one hand, we're given, effectively, a simple one-size-fits-all 180 heart rate formula that does not take into account anything substantive in the way of individual cardiovascular physiology - yet we're told that training volumes are largely and individual matter. OK, fine, but can you give me a suggestion for the minimums here? A range? Can I improve at such low heart rates training 3x a week for 30 minutes a day? No guidance. Let me save you some suspense here - unlikely. For a book about `racing', there's an almost total lack of any sort of even semi-structured program regarding durations and frequency for ANY sport (save one small and not very useful example of a triathlete schedule)- just a lot of sidebar anecdotes of people training for unspecified periods of time and having "success" or reducing volumes, when specified, from 18 to 12 hours a week (volumes far in excess of many amateurs I know). While it might vary from individual to individual and given your goals, I think we can all agree that training 1x/week for 1 minute will get you nowhere. So there, that's a lower boundary we can all agree on. Extreme case? Yes - but the point is one can and ought to give a lower limit from which to start a training program to see progress and then principles upon which to evaluate whether volume should increase or decrease.
* Heart rate variations are not thoroughly discussed. There seems to be this implicit and rather impractical notion that you can train up to the maximum prescribed heart rate and just hold it there - as if it is some number that can be reached and held. If my maximum "aerobic" heart rate, as prescribed by the 180 formula, is 140, I can guarantee you it will drift to 141, 142, even 144 and then back to 140, 139, 138 within any given 2 minute period of time - I know, I've seen it happen all the time. At such low heart rates, my body is so relaxed that if I so much as *think* about something a little exciting, my heart rate will spike. How much variation around my max Maff heart rate should be tolerated? We're told, none. So, given the natural variation in heart rate that occurs in training (i.e. I see +/- 3 beats, routinely), best to play it safe and shoot for Maff -3 so as not to exceed it for even a brief period. All in all, at such low heart rates, it is subject to considerable "noise" from your state-of-mind, thoughts, ambient temperatures, etc.
* Mis-use of the term "aerobic". Maffetone clearly defines what he means by "aerobic" early on to refer to that which uses predominately fat for fuel while fully acknowledging that, technically, sugar is burned aerobically as well. Nevertheless, anything that uses sugar, predominately, for fuel, is deemed anaerobic for purposes of discussion in the book. Fine. However, later in the book, he seeks to emphasize the value of his training principles by pointing out that the aerobic system provides 99% of the energy for long distance aerobic events. OK, wait a minute. Now, yes, that's true, but that involves both the sugar and fat burning systems (and sugar burning would actually account for a larger portion of that 99% than fat at higher intensity aerobic events) but he "implies" that it's the fat burning system providing that 99%. Let's keep the discussion about "aerobic" system straight here and acknowledge that the sugar-burning component IS a critical system for racing success as well.
* Results. Bottom line, if you train for modest volumes (read: 5 hours / week or fewer), I think your success will be modest at best. I conducted 95% of my aerobic training with Maffetone principles and, while I've seen some improvement, it was absolutely dwarfed, in comparison, by my prior success with programs such as Smart Coach provided by Runner's world wherein, training at more moderate intensities for most of my longer runs and doing just one speed workout a week resulted in a 9 minute improvement in my half marathon time in just 3.5 months of training (40s/mile improvement in pace). My average training week was only 18 miles/week (3 hours/week) when using the program prescribed by Smart Coach [and I weight trained....]. Compare that to training for 4-5 hours / week using Maff and I've seen - I don't know,....maybe 1-2 minutes of improvement for a half marathon- if you squint. In fact, Chris Carmichael has pointed out in his book "The Time-Crunched Cyclist" that, if you have less than 8 hours / week to train, traditional, lower-intensity programs just don't work for such folks. That's the only guidance I have right now and I would pass that on to those considering the Maff approach.
So, while I think there is some value here, I think a follow-on book with much more specific guidance is needed. Realistic training expectations need to be established based on possible training volumes. Actual training programs should be indicated with clear discussions of "frequency" and "duration" for running, cycling, swimming and triathlons. Different distances could be discussed as well. Given the size of this book, the actual intellectual content could have been condensed to 1/3 the size. That leaves 2/3rd of relative fluff that could have been used to address the aforementioned gaps in concrete training advice and coaching.
